Book Image

WordPress Plugin Development Cookbook - Third Edition

By : Yannick Lefebvre
Book Image

WordPress Plugin Development Cookbook - Third Edition

By: Yannick Lefebvre

Overview of this book

WordPress is one of the most widely used, powerful, and open content management systems (CMSs). Whether you're a site owner trying to find the right extension, a developer who wants to contribute to the community, or a website developer working to fulfill a client's needs, learning how to extend WordPress' capabilities will help you to unleash its full potential. This book will help you become familiar with API functions to create secure plugins with easy-to-use administration interfaces. This third edition contains new recipes and up-to-date code samples, including new chapters on creating custom blocks for the block editor and integrating data from external sources. From one chapter to the next, you’ll learn how to create plugins of varying complexity, ranging from a few lines of code to complex extensions that provide intricate new capabilities. You'll start by using the basic mechanisms provided in WordPress to create plugins, followed by recipes covering how to design administration panels, enhance the post editor with custom fields, store custom data, and even create custom blocks. You'll safely incorporate dynamic elements into web pages using scripting languages, learn how to integrate data from external sources, and build new widgets that users will be able to add to WordPress sidebars and widget areas. By the end of this book, you will be able to create WordPress plugins to perform any task you can imagine.
Table of Contents (15 chapters)

Displaying a calendar day selector using the Datepicker plugin

As you develop configuration interfaces for your plugins or meta boxes to associate data to custom post types, you may need users to enter dates in text fields. Instead of only relying on the user to correctly enter date information using simple text, a much more reliable data entry method is to use a pop-up calendar. This type of tool allows users to navigate through visual representations of each month and pick the desired date.

Getting ready

You should have access to a WordPress development environment.

How to do it...

Follow these steps to use the jQuery Datepicker script that is provided by default with WordPress to display a pop-up calendar to provide an easy way to select dates:

  1. Navigate to the WordPress plugins directory of your development installation.
  2. Create a new directory called ch9-calendar-picker along with a subdirectory called css.
  3. Visit and...